Commutating mechanism for ignition systems and the like



1,628,902 May 1927' "r. P. NICKELL ET AL COMMUTATING MECHANISM FOR IGNITION SYSTEMS AND THE LIKE Filed June 2, 1922 5141x244 ozs.

Patented May 17,1927.

UNITED STATES PATENT OFFICE.

THOMAS P. NICKELL AND WILLIAM H. RODEFELD, OF RICHMOND, INDIANA; SAID NICKELL ASSIGNOR TO ROBERT S. BLAIR, OF STAMFORD, CONNECTICUT.

COMMUTATING MECHANISM FOR IGNITION SYSTEMS AND THE LIKE.

Application filed June '2.

This invention relates to commutating mechanism and more particularly to mechanism of such nature of ignition systems of internal combustion engines. One of the ob* jects thereof is to provide mechanism of the above nature of simple and durable construe tion. Another object is to provide mechanism of the above nature of etlieicnt and dependable action. Other objects are to provide mechanism of the above nature which shall be inexpensive and practical. in a high degree and adapted to withstand long-continued use at high speed. Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly consists in the features of construction. combinations of elements and arrangement of parts which will be exemplified in the structure hereinafter described and the scope of the application of which will be indicated in the following claims.

In the accompanying drawing in which is shown one of various possible embodiments of this invention,

Figure 1 is an end view thereof partially diagrammatic; and

Figure 2 is a sectional elevation taken along the line 22 of Figure 1.

Similar reference characters refer to similar parts throughout the views of the drawing.

Referring now to Figure 1 of the drawinc", there is shown at 10 a shaft driven in this embodiment from an internal combustion engine at a predeterminedrate with respect to that of the engine crank shaft. The several wires 11 correspond to the cylinders of the engine. in this case four in, number, and these wires lead through an is nition system of a well known type such as that commonly used in Ford automobiles. As diagrammatically indicated at 12 they ultimately lead to ground.

The wires 1.1 as shown in the drawing terminate at binding posts 13 mounted about a stationary casing 14. It may here be noted that the term stationary is used herein in a broad sense to differentiate from a part which in operation is in movement. The casinq 14. although stationary in this sense adjustable as by means of the arm 15 about the axis of the shaft 10 with respect to which it is concentrically mounted. By this 1922. Serial No. 565,299.

adjustment the angular relation of the easing with respect to any given position of the shaft 10 may be varied, thus corresponding to a varying hexangular relation with respect to the crank shaft of the engine and cycles of its cylinders.

The binding posts 13 comprising metallic shanks 16 which pass through the walls of the casing are spaced therefrom as by the insulatinghushings 17 and sleeves 18. The outer end of the shanks are threaded to accommodate the lock nuts 19 between which the end member of the wires are gripped. At the inner end of the shank 16 is a contact member 20 integral therewith and having an inner surface 21 which is concentric with respect to the shaft 10. The sleeve 18 as shown in Figure lv of the drawing. fits the contour of the inner wall of the casing and the parts are rigidly held in this position by the inner nut 19 even though the outer nut 19 be loosened or removed in making: or breaking connection with the wire.

The casing 14 is provided between each contact 20 with a contact 22 which is electrically and mechanically connected there with. Thus these contacts 20 and 22 alternate about the casing and the inner surfaces of the contacts 22 as shown at are curved to complete a circle with respect to the curved inner surfaces of the contacts 21 and 22. There is thus provided a substantially continuous metallic raceway of a truly circular form and free from insulation other than that provided. by the air at the caps 24.

(lo-acting with these various contacts is a brush 25 fixed on the shaft l0. This brush comprises a hub 26 with a hollow boss 27 in which is slidably fitted. a contact member 28. The member 28 is urged outwardly as by a spiral spring 29 within the boss 27 and seated at its outer end in the inner surface of the contact as shown. The outer surface of the contact 28 is preferably sub stantially as indicated in Figure 2 of the drawinsr. In other words. it is curved to fit the circle formed by the surfaces 21 and 23 and is of such a length in a circumferential direction as to bridge the entire space be tween successive contacts 22. Thus it is in electrical connection with each contact 22 before it has broken electrical connection with the contact 22 which it is leavin Contact 28 may if desired be provided with a transverse recess 30 although this is not necessary in so far as the broad features of this invention are concerned.

Ihe casing Lt thus supports a series of contacts which are alternately grounded and live', the latteirtermxindicating a connection with a sourceot-electrical"potential.

In the action of the device, as thecontact travels about with the rotatuui oi" the shaft it passes over a continuous raccthe terms with respectto the direction of rotation. This. results from the tact that even. thoughcontact 28 has lettthe precedinc; contact 225% has before that time made engagement with the following contact and thus unlnterruptedly grounds the in- .termediate contact 20. This action takes place with the various contactsQO in succession and theen ine is thus properly fired. In this action furthermore, itis to be especially noted that there. is. no grounding through themoving parts or necessity of ad ditionalcontact mechanism to complete the circuit from the member. to ground. 'lhereisthus no occasionto ground through a bearing with its high resistance due tooil and its possibilitv or sparking. Furthermore, ball-bearings may be utilized without fear of high resistance. dueto their. point contact. The single connection, namely that formed between the member. 28 .and the various members mounted about the casing 14, is of the rubbing type, thus tending to main tain itself in etiicient low-resistance condition and is for the reasons above explained, durable and accurate. T he air insulation between the contactsis ample and the -device is thus not subjeetito .tlrewearingof insulation with attendant unevenness and tormation o't insulatingpowder.

It will thusbeseen. thatthere is provided a device of simple and inexpensive construction whichis well ZtClflDtQtttOzlllQt-Bt the hardest conditions of practical use.

As various possible embodiments .might be made of the above invention and. as various changes-might be made in the. embodiinent above-set fortlhitis to bennderstood that all matter herein set forth orshown in the accompanying drawings istto be interpreted as illustrative, andnot in a limitsense.

lVe claim as our invention 1. In mechanism of the general nature of that herein described, in combination, a pair of grounded contact: members, an interposed live contact member. and a lneiulmr adm ted to pass over the s1trlhces'ot sa id thrcc members and ot sullicicnt length to bridge from one to the o her l said Q oiuuliuo' members whereby said live u'icmbei. is maintained in electrical omicctiou with ,fll'Olltltl during the entire time of L'Ullljtltl' therewith o'l said, last member.

2.. In mechanism of the general nature of that herein described. in combinatitm. a pair of grounded members. an interposed live member the active surfaces or" all of which lie in the arc of a single circle. and a rotary member the active surface of which conforms to said are and is of sutlicient -len th to bride'e said :Irounded members- 3. In mechanism of the general nature of that herein desoribed, in combination, a ries of metal contact members having their active surfaces arranged in circular Form, and arotary contact member coactine' therewith and continuously engaging with a plurality of said first contacts and formed to bridge the space therebetwcen. the con tact members of said series being alternatolv live and grounded. and said rotary contact member being adapted to bridge adjacent grounded contacts.

4-. In mechanism of the general natureo'f that herein described. incombination. a pair of alternate live and wounded-contacts having their inner active surfaces arranged suhstantiallv in the arc of a circle and extending entirely about the circle spaced'one ut'rom another. anda rotary contact'member co-acting; withsaidinner surfaces and suc- CQSSIVQLV connecting said live members to the contiguous grounded members. said"1'otarv member beine of sutticient length in a circumferential direction to bridge successive grounded members and connect them one with another.

Inmechanism ot the .q-enerat nature oi that herein describedCin combination; a eas- .ing. a plurality of contacts spa ed about aid casing and insulated theretroin. a plurality ofco ntacts spaced about said casing alternatelv with respe t to said first-contacts. said several contacts baring their a tive surfaces lying in a circle. a rotary member mounted within said casino to rotate and successivelv connect said insulated. contacts with-the contacts adjacent thereto. and means 1 rain; said rotary 'member"outwardlv into eno'aecment WithtlidSUT'IOHlltlllliT contacts. said rotary member beinaot sutiicient lenoth in a circumferential direction to bridge successive grounded i-nembers and connect them one with another.

6min. mechanism oi" the general natureof ing, a plurality of contacts spaced about said iasing and insulated therefrom, a plurality of: contacts spaced about said casing alter nately with respect to said first contacts, said several contacts having their active surfaces lying" in a circle, a rotary member mounted within said casing to rotate and swrcssively minncct said insulated contacts with the contacts adjacent thereto, ignition wires leading to said hisulated contacts, and a ;.g;round connection from the contacts alternated therewith, said rotary mentiber being of sullicient length inv a circumferential direction to bridge successive grounded members and connect them one With another.

7. In mechanism of the general nature of that herein described, in combination, a casing, a plurality of contacts spaced about said casing and insulated therefrom, a plurality of grounded contacts spaced about said casing alternating with respect to said first contacts, said several contacts having their active surfaces lying in a single circle, and a rotary member mounted Within said casing coi'n 'irising a sliding contact adapted 'to slide over said active siiirfaces of said sev eral contacts and being of sufficient; circum-- ferential length to bridge successive ground ed contacts.

In testimony whereof, We have signed our names to this specification this 23d day of May, 1922.

THOMAS P. NICKELL. WILLIAM H. RODEFELD. 

